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New Space Combat System (I hope)

OK, after reading through T4 space combat (and noticing that it was very abstract and also very confusing) i decided to make my own. Now, having never run (or played) Traveller before, this will be flawed, which is why I'm posting it before I actually use it. The method has bits nicked mainly from Star Fleet Battles and Battletech.
First of all, combat takes place in hexes. What used to be one range band is now three hexes. Thus anything that could before fire at something with Very Short range can now fire at something up to three hexes away. Turns act in the following manner:
1. Sensor lock on - ships try to lock onto each other for the turn. Usual rules for lock-on apply.
2. Movement and Weapon Fire.
a). Movement is now divided into about 10 impulses (yes, grabbed right from SFB if u recognise it). Basically, each ship moves equal to its G rating every turn. It does this by moving one hex, or turning one hex side, once every impulse for a number of impulses equal to its G rating. e.g. a ship with a G rating of 5 would be able to move one hex or turn one hex side in impulses 1,3,5,7 and 9, for a total of 9 moves. I'll make up a table for this later.
b). Weapon fire happens here. So you get to fire ten times per turn, and have to check for sensor lock-on etc once every turn (i.e. every ten shots) I might change it to once every two impulses or something, so that someone who doesn't lock on isnt stuck for ten impulses with nothing to fire at. Also, you could (possibly) lock onto a number of targets equal to your ship's Fire Control Rating, so if a ship is destroyed you aren't sitting there twiddling your thumbs for the rest of the turn. Damage isn't applied yet - firing is basically simultaneous.
c). Damage Resolution. Now all damage (and external/internal hits) is applied. Penalties etc are put onto ships, if the manoeuvre drives are hit, the ship will lose G's (not sure whether this should take place at the end of the turn or at the end of the impulse).
3) End of turn. Anything like breaking off, pursuit, etc, can be dealt with here.

I also have an idea for External hits, but I'll leave that until I can get the wrinkles in this part of it ironed out. All feedback welcome.
Before you go to all the work (enjoyable as creation is) of creating a working system I'd recommend "The Role-Playing Space Combat System" put out as a free for use download (pdf I think). Copyright 1996 by Joseph E. Walsh. Collaboration by Eris Reddoch, Guy "Wildstar" Garnett (who did the great QSDS, also a download, and there was even a JAVA applet somewhere, which if you can find fixes the T4 ship design system), and Allen Shock. It was created for T4 and though I never gave it a thorough play I recall it worked great in the solo test run through.. Unfortunately I lost my saved copies and source bookmarks in a hard drive crash. Maybe somebody here or on the TML has a copy archived (backup, backup, backup, sigh, when will I learn to stop trusting technology). I do still have printed versions but no easy way to transmit them. I wouldn't mind finding the electronic versions myself again though I'll have to see how T20 works before knowing if I'll need them.
If you're looking for another impulse based space combat system (as opposed to the vector combat system Traveller tends to use), take a look at Full Thrust from Ground Zero Games, which is a miniatures space combat system. The Full Thrust group on YahooGroups has a conversion for FT->Traveller. Full Thrust also has optional rules for a vector thrust system.
It's not clear to me from your description how you account for residual momentum. Remember, a ship's G rating isn't an indication of how fast it moves, but rather how quickly it changes velocity. Thus, a 1G ship with a '20 hex' velocity last turn will move min 19 or max 21 hexes this turn (depending on how she spends her 1G 'burn'). And then there's the matter of adding/subtracting angle vectors for direction changes...
Hey Thorog,
I found myself in the same predicament after reading the T4 space combat rules. T4's space combat rules are very similar to highguard(ct-book 6). Like you , I invented my own rules, based loosly on Starfleet battles. Something you should keep in mind, when using SFB, is combat takes place in warpspace. Traveller space combat takes place at sublight speeds.

SFB Does come with a 10 impulse chart. I used it because in ct-book 2 turns are ten minutes long. Each impulse is one minute in a ten minute turn. Because each impulse last one minute, and each character combat round last 15 seconds(ct-book 1) Your player characters can get in four rounds of shipboard action( repairing damaged systems, helping injured shipmates, or repelling boarders)each impulse of your ten impulse turn.

So you see , I ended up combinig book 2 with SFB, and I had to tweak both. My turn sequence runs like this:
sensor Lock-on (Unles you've taken sensor damage you will usually lock-on)
Initiative determination (I took this from STARFIRE Both opposing captains roll a die highest roll wins. winner moves last and shoots first. loser moves first and shoots last)
Movment (according to who won initiatve) Since ships in traveller almost never exceed 6gs accel you can use movment rules from STARFIRE, If you don't care to calculate vectors. If you do care to calculate vectors, remember acceleration is the rate at which a ship changes velocity, and thus the number of times it gets to move on the impulse chart.

Weapons fire (initiative order)

Damage resolution (here the internal or external explosion tables are used)

Now you're ready for the next turn. the nice thing about house rules is you can adjust them to your taste.......
Hope this helps......
Hmmm...pity my SFB box only came with a 32-impulse movement sheet. The other problem is that if we do use 6 G's as maximum acceleration, then if someone decides to accelerate fully two turns in a row, they will be up to a movement of 12, which make the 10-impulse chart redundant (and believe me, our RP group will do this, just to see what I do). The only way I can think of doing it is using the 10-impulse chart, but allowing ships of velocity >10 to move twice in some impulses. Logic tells me to make the double moves go from the middle of the turn outwards, so a ship with movement 12 would move 1,1,1,1,2,2,1,1,1,1 hexes per impulse for the turn. Would you be able to post the impulse chart?
You should have a ten impulse chart mine is printed on the same page, with a twenty impule chart. Does your version have a twenty impulse chart?...

Here's the ten impulse chart you asked for...........

ship speed 10 9 8 7 6 5 4 3 2 1
1 - - - - - - - - -
2 1 1 1 1 1 - - - -
3 2 2 2 - - 1 - - -
4 3 3 - 2 2 - 1 - -
impulses 5 4 4 3 3 - 2 - 1 -
6 5 - 4 - 3 - - - -
7 6 5 - 4 - - 2 - -
8 7 6 5 - 4 3 - - -
9 8 7 6 5 - - - - -
10 9 8 7 6 5 4 3 2 1
My set (which i think is older) came with a 32-impulse move chart only. OK, I would prefer to 'invert' the 10-impulse chart (i.e. go from impulse 10 down to 1), which gives the faster ships (which we can assume to have a higher G rating) a slight edge in moving last. For ships moving faster than 10 Gs, they can use two rows in the chart (e.g. a ship moving at 16 Gs would use the 10 row and the 6 row, resulting in moves of 2,2,1,2,1,2,2,1,2,1 for the ten impulses using the inverted chart).
Oh, I don't know
Unless you bought yours Before 1979, I think My set is older. As for ships that move faster than ten Gs you can use the twenty impulse chartif you like I post it and I'll try to make it neater this time....
Hmmm...but if we say 'if the ships goes faster than...' we'll end up with a 50-impulse turn before long...and that's no fun since someone without sensor lock at the start of the turn is going to be very annoyed by about impulse 25. That's why I'm sticking with 10 impulses.
OK, so movement is done. I'm asuming the turn will run something like this:
  • Initiative
  • Sensor lock-on
  • Move and Fire (in impulses)
  • Damage resolution
Let's go through the steps one at a time.
Initiative: roll a D6, add fleet leader's Tactics score (or the captain with the highest tactics score if there isnt a fleet leader). Highest roll wins. Since movement is pretty much simultaneous, G ratings shouldn't bother it at all. Any feedback on this?
I was actually thinking of doing it so that the side with initiative moves last...in the sides you can move ships however you wish...since faster ships automatically move later than slower ones. BTW when i said feedback, I was actually meaning about initiative. There should be some advantage to having a 'flagship' as such. Something like rolling 2D, subtracting the result from tactics+edu of the leader of the flagship and using it as a modifier for every other leader? At low levels (e.g. tac 2 edu 6) this is tricky, as it is easy to roll over and give everyone negative mods. But later on (e.g. tac5 edu 6) you're going to roll under most of the time and give everyone +1 to +9 to their rolls...we might want to cap it at +5 or something...
OK, onto sensors.
I prefer the Role-Playing Space Combat system to the standard Traveller system. I have only made a few alterations to it here. Passages marked in asterisks (* *) are debatable, and which we may want to change
A ship may choose to use active or passive sensors. If it uses active sensors, *it is automatically detected by all ships*. If it uses passive sensors, it can use its active sensors to jam (*change so that ships can jam all the time?*) enemy sensors. The difficulty to detect an enemy ship increases with range:
Range Difficulty Dice
V Short Average (2D)
Short Difficult (2.5D)
Medium Formidable (3D)
Long Staggering (3.5D)
V Long Impossible (4D)
The target number is as follows:
With active sensors:
your ship's Active Sensors rating
- the enemy ship's Jam rating (if they are jamming
-3 if enemy ship is using EMM
With passive sensors (*should you be able to detect passive ships with passive sensors?*)
your ship's Passive Sensors rating
+ enemy ship's Jam rating (if they are jamming - note this is a bonus)
-3 if enemy ship is using EMM
Once one ship in a side has sensed a ship, the rest of the fleet can use this information, except for ships with damaged communication equipment. They cannot get enemy ship information from allies, nor can they pass sensor information on to others. Detecting each ship counts as an action, thus trying to detect two or more ships counts a multiple actions. Failing to sense a ship means that any attacks on that ship are made at one difficulty level higher than usual.
If you do not have a sensor lock on of a ship, how can you possible hit it except at point black range? The combat ranges will make the actual targeting angle thousandths of a degree. At the speed of light, just how far will that ship move across the target aim point when you consider how far apart they are.
The 15 minute combat turns in CT are still a source of amusement.

In the end,Murphy will rule
Originally posted by vegascat:

The 15 minute combat turns in CT are still a source of amusement.
It ends up being one of those scary little things. The T20 space combat system has 20 minute turns.

The problem comes down to, if starships are far enough apart so that a laser does not automatically hit when fired, they are far enough apart to either require big hexes for movement, or a lot of hexes. So your choices are:

1. Small Hexes, short turns, ships can dodge but the ranges are 1000s of hexes (or more).
2. Large Hexes, long turns, ships can dodge lasers.

So the odd long turns becomes the sacrifce before the god of simple game mechanics.
Starship combat turns in ct are TEN minutes long...
My intention IMTU was that ten minute ship combat turns , take place over ten one minute impulses, in which characters onboard get FOUR fifteen second ct book one character combat rounds...

I hope this clears things up......
Originally posted by soloprobe:
Starship combat turns in ct are TEN minutes long...
Well... actually they are 1000 second (16.6 mins.) turns, at least in The Traveller Book. I suppose you could round it to 10 mins., or 20 mins., I think we did 15 mins. in our games.

Anyway it's a fairly moot and mutable point
I'm all for using what works best.
Originally posted by far-trader:
</font><blockquote>quote:</font><hr />Originally posted by soloprobe:
Starship combat turns in ct are TEN minutes long...
Well... actually they are 1000 second (16.6 mins.) turns, at least in The Traveller Book. I suppose you could round it to 10 mins., or 20 mins., I think we did 15 mins. in our games.

Anyway it's a fairly moot and mutable point
I'm all for using what works best.

It appears that there were a number of revisions along the way. My first edition copy of Book 2 does show a starship combat turn to be 10 minutes long, and scale is 1:63,360,000 (1' = 1,000 miles)....Hmmm...that reminds me of a post I recently read somewhere else where they were complaining that GT's conversion of scale to the non-metric units of measure bordered on heresy....guess they haven't been playing as long as we have. ;)

It appears that I have misplaced my Traveller Book hardback, so I don't have it available for comparison.

Speaking of changes between printings, Book 5 (first printing - 1979)has three ranges (Long, short & very short/boarding). The follow-on printing (1980) only lists long and short. The former provides a scant three paragraphs (4 if you count the paragraph under range determination), whereas the latter has a complete, dedicated section.

All that said, having played Traveller:2300 (later retitled as simply 2300AD), I had already cut my teeth on the system that would eventually grow into the New Era's Brilliant Lances. And I too eventually migrated to "The Role-Playing Space Combat System". An evolution which was definitely an improvement.

Originally posted by tjoneslo:
The problem comes down to, if starships are far enough apart so that a laser does not automatically hit when fired, they are far enough apart to either require big hexes for movement, or a lot of hexes.
I run into this problem ALOT with my new players and even the non-technogeek veterans. Its sometimes frustrating to inform your "pilot" that the pirate ship is "thirty light seconds behind you, and gaining"... only to have the poor player start sweating out evasive manuevers because the bogie is "right on top of us".

Its the nature of the tech assumed by the game. Weapons reach very far out there, but even the fastest ships only maneuver at 6g's. Makes for very long and drawn out fights.

I've often considered assuming a faster maneuver drive IMTU, and we've bounced around a few differing ideas while trying to keep the game "still Traveller".

We played around with the SFB impulse type movement, but that chart was intended for velocity based movement, not acceleration. Accleration based movement will always be able to leave the chart eventually.

The current system we are using is velocity based... the ship's maneuver drive rating gives it the atmospheric speeds listed in the books, and surface to orbit times are computed from that.

Once in space, we're using maneuver drive rating = hexes per three minute turn (one hex = 30,000km)... VERY FAST. A ship can make a number of hex side turns equal to its agility +1 in a given turn, unless its "stationary"... then it can turn up to three sides. A ship can accelerate or decelerate its entire current drive rating in one turn.

Its a serious hand-wave, and we're breaking all kinds of rules of physics... but it was a solution that my english teacher players could understand and my physics professor/engineer players were able to tolerate. Its also not too far off in practice from stutterwarp was in T2300.

Oh yeah, we haven't yet figured out what we're going to do about the 100 diameter safe jump thing yet. Even a slow merchant can pull that off in short order.